Of all the 190 countries where Microsoft’s Windows 10 operating system launched yesterday, Microsoft CEO Satya Nadella chose to spend the day in Kenya. His visit came just days after the conclusion of the US-sponsored Global Entrepreneurship Summit and a state visit by president Barack Obama, where he hailed technology for “changing the way Africa is doing business.”

Nadella’s choice seems a strange one in some respects. Not everyone thinks Kenya’s so-called “Silicon Savannah” is poised for a revolution. “The technology opportunity has been overblown in the international media,” David Loew, a manager at Open Capital Advisors, an advisory consultancy in Nairobi told Techcrunch this week.

A 16% value-added-tax on imported electronics was imposed in 2013; it dented sales, even as they grew in other nearby countries. Startups are often short on cash: A survey last year of more than 230 Kenyan startups found that 70% of them were not earning enough to maintain their business and living expenses and less than 9% (pdf, p. 48) got venture-capital funding last year. Some worry that Kenya, which is building a $14.5 billion “tech city” south of Nairobi in the town of Konza, is getting ahead of itself.

However, local entrepreneurs say that new mobile- and internet-focused businesses are now beginning to hit their stride, taking advantage of cheap internet, a growing pool of talent, and consumers’ increasing trust in new internet and mobile-phone based services, thanks to the ubiquity of the mobile money transfer system, M-Pesa.